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View Full Version : does anyone know how to clean the rust off a lens chuck?



phillip2446
19-Mar-2014, 17:24
i bought a large lens chuck here awhile ago and it came with a lot of rust on the blades. can anyone recommend a way to take off the rust without ruining the blades.
thanks

Jac@stafford.net
19-Mar-2014, 18:20
Presuming you are writing about a universal lens mount (iris type), then the blades are quite robust. I have restored two by using a rust remover and tooth brush. Clean in mildly diluted detergent and dry thoroughly, then thinly coat with a light oil, then dry with a micro-fiber cloth. If you have compressed air it helps with the later two operations.

phillip2446
19-Mar-2014, 19:21
thanks. any particular brand of rust remover?

Jac@stafford.net
19-Mar-2014, 21:06
thanks. any particular brand of rust remover?

Evapo-Rust is good stuff. Just soak the whole thing in a shallow pan for several minutes, wipe with toothbrush, repeat.

When the rust is all gone, I apply a little oil on the blades, and work them open and closed, then wipe dry just for my own peace of mind. It is not really necessary.

Steven Tribe
20-Mar-2014, 02:42
These are made in quite a few designs.
Most are easily taken apart (and reassembled!). There are not too parts to keep tabs on.
Apart from removing surface rust, it might be a good idea to straighten the individual blades and lubricate the turning and locking mechanisms.

I have suggested this be moved to DIY!

Struan Gray
20-Mar-2014, 05:20
The one I have, and others I have handled, have had the steel blades blued to resist corrosion. If you have a metal shop nearby (or are not afraid of home chemistry) re-doing the blueing might be good for preventing further rust. The only real issue is making sure that whatever is holding in the pivot pins is not damaged by heat or caustic chems - a brazed pin, for example, might not cope with prolonged immersion in strong acid/alkali.

goamules
20-Mar-2014, 05:56
Vinegar diluted about 50% with water works well for rust removal. Just soak it for about 1 hour at first, and see if that does the trick. Use a little 0000 steel wool. It's metal, you're not going to hurt it any more than the rust already did. But don't soak it for days, the acid could eventually pit the metal a little. Though the rust already did that. Oil is always used on blued metal to avoid rusting. But if the tool was in a damp basement for decades, etc, it will eventually wear off.

toolbox
21-Mar-2014, 08:07
Google "electrolytic rust removal"...all you need is an automotive type battery charger and some washing soda. I've used it when restoring my Teletype model 15...works great! I usually dry metal parts in my toaster oven (I have one that lives in my shop). Set it for 150* for about 10 minutes, and that will usually do the trick. An air compressor or hairdryer works too.

AtlantaTerry
22-Mar-2014, 02:22
Instead of oil (which can attract dust then get messy) why not use a dry lube such as molybdenum disulfide?

Jac@stafford.net
22-Mar-2014, 08:09
Instead of oil (which can attract dust then get messy) why not use a dry lube such as molybdenum disulfide?

The powder is super invasive - it can move into your lens and possibly the camera. It is horribly difficult to remove.
.

John Koehrer
22-Mar-2014, 20:31
Instead of oil (which can attract dust then get messy) why not use a dry lube such as molybdenum disulfide?

You're not lubricating it just protecting the metal from rusting.

Steven Tribe
23-Mar-2014, 04:19
There is a thread in DIY (last post 2012) about repairing the the Universal iris clamp.

phillip2446
14-Apr-2014, 07:41
hi jac. what kind of oil do you use to on the blades? thanks
phil

Jac@stafford.net
14-Apr-2014, 09:51
hi jac. what kind of oil do you use to on the blades? thanks
phil

Because I had so much at hand, I used Mobil 1 5W-something synthetic and then blew the blades dry with compressed air. I would never do the same to a lens iris. The universal iris lens mount is far more robust.

phillip2446
15-Apr-2014, 17:19
so far....
i soaked the iris in CLR to remove the majority of the rust of the blades.
i then washed off the CLR with water (which was not the best move) then i let it air dry which caused the gears to move more clunky so i knew something was wrong.
the metal turned white which looked like it corroded in a different way
i am soaking the iris in wd-40 for about 24 hours then i am suppose to blow off the wd-40.
i don't have a tank with an air gun. can i use a can of compressed air for this.
then i am suppose to apply some sewing machine oil on the gears and blades then blow dry that off too.
hoping this is correct.

Steven Tribe
15-Apr-2014, 23:20
I would suggest you dismantle the iris - after this treatment, the turning gears could do with some fresh blobs of grease.

Jac@stafford.net
20-Apr-2014, 10:57
I would suggest you dismantle the iris - after this treatment, the turning gears could do with some fresh blobs of grease.

I agree but some of them, mine included, are riveted. Not everybody has a drill press with rivet grinder.

Or am missing something that should be obvious?

Steven Tribe
21-Apr-2014, 13:40
All 5 I have serviced had a pressure plate system on the leaves, that held it together. This was held in place by 4 screws that had washers that fitted into recesses in the lens board mounting lugs.

sun of sand
24-Apr-2014, 15:32
Naval jelly

I make my own using a drink thickener Simply Thick and Driveway acid etch precleaner stuff
concentrated Phosphoric acid and xanthum gum ..I will add some photo-flo to it after mixing it to a thickness appropriate for the job

It won't eat the metal to any degree even after a couple days
Areas where it was rusted will turn black protecting from future rust ..a little. Enough for this sort of thing.

I'd naval jelly for 5 hours then rinse in baking soda solution then distilled water then alcohol then blow it out and dry with cloth then blow again with a hairdryer

phillip2446
25-Apr-2014, 05:12
lots of neat tricks for cleaning this. thanks.